1. Field
The present disclosure is directed to a method and apparatus for ultrasonic triggered audio reduction.
2. Introduction
Presently, portable electronic devices include cellular phones, smartphones, tablet computers, MP3 players, and other portable electronic devices that output device audio through headphones for a user. For example, a smartphone device plays music, plays movies, streams music and movies, provides phone call audio, outputs game audio, provides white noise applications that output white noise audio, and provides other audio through headphones. Many of these headphones are in-ear and over-the-ear headphones that provide sound isolation from external noises. The headphones can also employ noise reduction that further blocks external noises.
Unfortunately, the combination of device audio, sound isolation, and noise reduction prevents the user from clearly hearing external audio that is of interest to the user. For example, a user riding a train can listen to device audio using headphones that muffle or block most external audio, including outside noise. The muffled or blocked external audio also includes any public announcements from a public address system on the train. The user may hear some sound from an announcement, but may not bother pausing the audio or taking off their headphones to listen to the announcement. Even if the user does pause the audio or take off the headphones, it may be too late to hear the announcement. This problem also applies to emergency alerts and announcements made on other public address systems. It also applies to emergency vehicle alerts, tornado alerts, and other public alerts that should be heard over the portable device music. If a user misses the external audio alerts, the user may miss their train or bus stop, may not take appropriate action in response to emergency warnings, and will not otherwise timely and appropriately respond to the announcement.
Thus, there is a need for a method and apparatus for ultrasonic triggered audio reduction.